$A$ sensitive magnetic instrument can be shielded very effectively from outside magnetic fields by placing it inside a box of

In a ferromagnetic material,below the Curie temperature,a domain is defined as:

Which of the following materials exhibits diamagnetism?

If $\chi$ stands for the magnetic susceptibility of a substance, $\mu$ for its magnetic permeability, and $\mu_0$ for the permeability of free space, then which of the following is correct?

Statement $I :$ The ferromagnetic property depends on temperature. At high temperature,a ferromagnet becomes a paramagnet.
Statement $II :$ At high temperature,the domain wall area of a ferromagnetic substance increases.
In the light of the above statements,choose the most appropriate answer from the options given below :

The susceptibility of a magnetic material is positive and small. The material is